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Nikon has set out to widen the full frame DSLR market with a two-pronged strategy embodied in the new D600. Name the two things that work against full-frame DSLRs and they have to be physical bulk and cost. The D600 takes on both of these issues and at first glance it looks like Nikon has hit its targets. The D600 is the smallest and lightest full-frame DSLR yet and it is one the most affordable.